Abstract
This paper describes a method for obtaining stress-strain characteristics of rigid PVC resin under such conditions that are encountered in a deformation zone of that cutting. For this purpose, the impact-compression testing machine is employed, which includes a special stopring which enables to control strain increments during each impacts. The experiments are carried out under strain range 0-0.7, strain-rate range 10-3-103 s-1 and temperature range 0-120°C for rigid PVC resin. The main results of these experiments are summarized as follows: (1) Flow stress of PVC is not influenced by the strain rate history and temperature history. (2) The flow stress of rigid PVC resin may be expressed as
σ=σ0(ε/ε0)m(ε/ε0)n exp(-αθ)
where ε, ε and θ are total strain, total strain rate and temperature, respectively. ε0, ε0 and σ0 are referenced values of strain, strain rate and stress, respectively. m, n and α are constants at temperature less than 80°C, but they change at temperature higher than 80°C. (3) The relationship between plastic strain εp and total strain ε on rigid PVC resin is expressed as
εp = 0.89ε-0.07.
